The present invention relates to packaging machines, and more particularly to a machine adapted to fill a fluid food or like contents into containers and thereafter close the containers while the containers are being transported by a conveyor.
Conventional packaging machines of the type mentioned comprise a container transport conveyor, and a group of devices arranged in series along the path of travel of the conveyor for filling contents into containers each covered with a thermoplastic resin over its outer surface and thereafter closing the containers. The conveyor has container holders each adapted to hold the container so that the container is restrained from moving horizontally while being allowed to move vertically, and a rail extending below and in parallel to the path of movement of the container holders for supporting the bottom of the container held by each holder to guide the container. The group of devices includes a heater for applying hot air to the container for sterilization or heat sealing.
It is likely that the hot air from the heater will heat not only the container but also the rail. The thermoplastic resin covering the outer surface of the container then adheres to the rail upon melting due to the heat of the rail, giving rise to the problem that the adhering resin offers resistance to make the rail unable to guide the container smoothly. The adhesion of the resin also involves the problem of being undesirable for sanitation.